I highly recommend DangerDen, I purchased a P4 waterblock from them and was very satisfied (prompt delivery, good ordering system, etc.). I built my own system (do a search for a post titled "Pics of my homemade watercooling setup). However, for a system designed to be totally inside a case, you can't beat the systems they sell at DangerDen and the like. The Eheim pump is the ONLY way to go for an in-case system so you may as well just buy a complete kit and save money. If you are building an external system you can get the cheaper Danner utility pump (Supreme Mag-Drive) from a pond supply store and the 350GPH model I have of this pump is a bit stronger than the eheim (10' of pump lift) but it is a bit louder (makes a low pitch hum). However, it is far too big to be used inside a case, and the bigger problem is that it generates quite a bit of electromagnetic interference so you don't wanna have a utility pump too close to your monitor or hardware or you might have issues. The same goes for the radiator. You can get a heatercore from an autoparts store, and it will flow better than any computer radiator on the market, BUT it's too big to put in a case. So in your situation, you can't beat a complete kit. Also, if you want to build your own system, keep in mind that the hardware adds up. At $2 per brass fitting and $1 per hose clamp, you can easily spend $60 at Home Depot just buying fittings...